Electronic motor vehicle control devices, such as, for example, ABS and/or EBS brake control devices, often comprise redundant signal processing systems in order to be suitable for modern safety-relevant applications. In this case, the requirements on the components are steadily increasing. As the complexity of the individual components increases, however, so does the possibility of malfunctions. Due to the increasing requirements on the components, for example, control devices, the components are produced according to specified safety regulations.
One example of an antilock vehicle brake system is known from DE 32 34 637 C2. In this case, the input data are fed in parallel to two identically programmed microcontrollers and are synchronously processed there. The signals are compared in-between and at the output. If a deviation of the signals from one another occurs, a shut-off signal is output. Due to a second microcontroller, which is identical to the first microcontroller in terms of its design and its programming, at least some data processing errors can be detected. Such a system requires two high-quality microcontrollers, however, even though a single microcontroller would suffice for generating the actual control signals, whereby the expenditure for microcomputers doubles due to safety reasons.
To rule out a possible source of errors due to a system design error or a system production error of the microcontroller, the two systems would also have to be developed by independent programmers, whereby the expenditure increases even further.